SGD Paper Help



Yuga M, et al.  (2011) Aspartyl Aminopeptidase Is Imported from the Cytoplasm to the Vacuole by Selective Autophagy in Saccharomyces cerevisiae. J Biol Chem 286(15):13704-13

Abstract: Macroautophagy is a catabolic process by which cytosolic components are sequestered by double-membrane vesicles called autophagosomes and sorted to the lysosomes/vacuoles to be degraded. Saccharomyces cerevisiae has adapted this mechanism for constitutive transport of the specific vacuolar hydrolases aminopeptidase I (Ape1) and alpha-mannosidase (Ams1); this process is called the cytoplasm to vacuole targeting (Cvt) pathway. The precursor form of Ape1 self-assembles into an aggregate-like structure in the cytosol, which is then recognized by Atg19 in a propeptide-dependent manner. The interaction between Atg19 and autophagosome-forming machineries allows selective packaging of the Ape1-Atg19 complex by the autophagosome-like Cvt vesicle. Ams1 also forms oligomers, and utilizes the Ape1 transport system by interacting with Atg19. Although the mechanism of selective transport of the Cvt cargoes has been well studied, it is unclear whether proteins other than Ape1 and Ams1 are transported via the Cvt pathway. We describe here that aspartyl aminopeptidase (Yhr113w/Ape4) is the third Cvt cargo, which is similar in primary structure and subunit organization to Ape1. Ape4 has no propeptide, and it does not self-assemble into aggregates. However, it binds to Atg19 in a site distinct from the Ape1- and Ams1-binding sites, allowing it to ''piggyback'' on the Ape1 transport system. In growing conditions, a small portion of Ape4 localizes in the vacuole, but its vacuolar transport is accelerated by nutrient starvation and it stably resides in the vacuole lumen. We propose that the cytosolic Ape4 redistributes to the vacuole when yeast cells need more active vacuolar degradation.

Status: Published Type: Journal Article PubMed ID: 21343297

Topics addressed in this paper

Number of different genes curated to this paper: 6

  • To find other papers on a gene and topic, click on the colored ball in the appropriate box.
  • displays other papers with information about that topic for that gene.
  • displays other papers in SGD that are associated with that topic.
    The topic is addressed in these papers but does not describe a specific gene or chromosomal feature.
  • To go to the Locus page for a gene, click on the gene name.
Topics Genes linked to topics
AMS1 APE1 APE4 ATG1 ATG11 ATG19
Additional Literature blue ball blue ball blue ball blue ball
Cellular Location blue ball
Primary Literature blue ball blue ball
Protein Processing/Modification/Regulation blue ball
Protein Sequence Features blue ball
Protein-protein Interactions blue ball blue ball
Strains/Constructs blue ball blue ball blue ball blue ball blue ball blue ball

Author Searches

To find contact information or other publications by the authors of this paper, follow these three steps:
  1. (1) Choose an author,
  2. (2) Choose a search parameter,
  3. (3) Click to implement